Managing the Python path

pytest needs to be able to import the code in your project. Normally, when interacting with Django code, the interaction happens via manage.py, which will implicitly add that directory to the Python path.

However, when Python is started via the pytest command, some extra care is needed to have the Python path setup properly. There are two ways to handle this problem, described below.

Automatic looking for Django projects

By default, pytest-django tries to find Django projects by automatically looking for the project’s manage.py file and adding its directory to the Python path.

Looking for the manage.py file uses the same algorithm as pytest uses to find pyproject.toml, pytest.ini, tox.ini and setup.cfg: Each test root directories parents will be searched for manage.py files, and it will stop when the first file is found.

If you have a custom project setup, have none or multiple manage.py files in your project, the automatic detection may not be correct. See Managing the Python path explicitly for more details on how to configure your environment in that case.

Managing the Python path explicitly

First, disable the automatic Django project finder. Add this to pytest.ini, setup.cfg or tox.ini:

[pytest]
django_find_project = false

Next, you need to make sure that your project code is available on the Python path. There are multiple ways to achieve this:

Managing your project with virtualenv, pip and editable mode

The easiest way to have your code available on the Python path when using virtualenv and pip is to install your project in editable mode when developing.

If you don’t already have a pyproject.toml file, creating a pyproject.toml file with this content will get you started:

# pyproject.toml
[build-system]
requires = [
    "setuptools>=61.0.0",
]
build-backend = "setuptools.build_meta"

This pyproject.toml file is not sufficient to distribute your package to PyPI or more general packaging, but it should help you get started. Please refer to the Python Packaging User Guide for more information on packaging Python applications.

To install the project afterwards:

pip install --editable .

Your code should then be importable from any Python application. You can also add this directly to your project’s requirements.txt file like this:

# requirements.txt
-e .
django
pytest-django

Using pytest’s pythonpath option

You can explicitly add paths to the Python search path using pytest’s pythonpath option.

Example: project with src layout

For a Django package using the src layout, with test settings located in a tests package at the top level:

myproj
├── pytest.ini
├── src
│   └── myproj
│       ├── __init__.py
│       └── main.py
└── tests
    ├── testapp
    |   ├── __init__.py
    |   └── apps.py
    ├── __init__.py
    ├── settings.py
    └── test_main.py

You’ll need to specify both the top level directory and src for things to work:

[pytest]
DJANGO_SETTINGS_MODULE = tests.settings
pythonpath = . src

If you don’t specify ., the settings module won’t be found and you’ll get an import error: ImportError: No module named 'tests'.